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NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Mon Jan 22, 2018 18:34
by subpixel
It seems that Resolume may be using the wrong alpha type (straight vs premultiplied) for an NDI source coming from Adobe After Effects (CC 2017).

There is no Alpha Type option for the NDI source. Perhaps one is needed.
2018-01-23 Tue - After Effects NDI Resolume - bad alpha.png
The sample screenshot shows smooth gradients and edges on the bubbles in AE (on the right) and the left is a full-screen Advanced Output slice on an external screen. New composition with just the NDI source loaded in Layer 1.

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Mon Jan 22, 2018 19:06
by subpixel
I tried the Spout AfterEffects CC2017 plugin as a comparison; in Resolume the Spout Server source has an Alpha Type option. The default setting, Premultiplied, produces the correct result. The Straight alpha type option produces a bad result that looks like the sample NDI capture in the original post.
2018-01-23 Tue - After Effects Spout Resolume - premult alpha.png
Premultiplied = good :)




2018-01-23 Tue - After Effects Spout Resolume - straight alpha.png
Straight = bad :(

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Fri Jan 26, 2018 13:41
by Daniel
hey subpixel,

We indeed only accept premultiplied at the moment on NDI. But for some reason, it is showing the straight optioned compared to spout.

EDIT:

I've tested the Spout option and with straight it indeed seems not be working completely fine. I'm not getting the same results as you with white borders. But I'm not getting the results that I'm expecting.

We will look into it and in the meanwhile, I would suggest to keep it on premultiplied with Spout

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Fri Feb 16, 2018 23:30
by daveg
I'm also getting the white outline (and compressed image) as if it were straight rather than premultiplied. I noticed it after I did the most recent update to v6.05. And definitely need that to work as intended! Has this been narrowed down to a Resolume issue? (not that I'm upset! love Resolume! just trying to find a way to fix this and still use NDI).

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Fri Apr 06, 2018 04:02
by francoe
I notice the same issue with alpha on advanced output, when you send a screen to ndi.

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Fri Apr 06, 2018 04:05
by francoe
Since first time with resolume, allways asked to myself: why isnĀ“t there a multiply filter? Why? :(

Re: NDI Source with alpha - wrong alpha type? | v6.0.3

Posted: Fri Apr 06, 2018 09:18
by Joris
Since the first time you asked that question, I always ask myself: does he not know that's exactly what Solid Color Effect with Show Image does?